Power hammer



Nov. 27, 1923. 1,475,763

G. FRASER POWER HAMMER Filed March 10. 1922 2 Sheets-Sheet 1 132%71307-Wafie/ Aiz q- G. FRASER POWER HAMMER Nov. 27 1923.

' Filed March 10 1922 2 Sheets-Sheet 2 Patented Nov. 27, 1923.

warren stares GEORGE FRASER, 0F LEVEN, SCOTLAND.

3901*? EB. HAl'vIMER.

. Application filed March 19, 1922. Serial No. 542,713.

To all whom it may concern.

Be it known that l, GEORGE FRASER, a citizen of the United Kingdom ofGreat Britain and Ireland, and resident of Parkhill Smithy, Park lVynd,Leven, Fife, Scotland, have invented certain'new and useful Improvementsin and Relating to Power Hammers, of which the following is a specification, such as will enable others skilled in the art to which itappertains to make and use the same.

This invention relates to power hammers of that type in which the hammeris driven from a crank the shaft of which can be coupled to anduncoupled from the driving agent by a gear controlled from a foot lever.

In my machine the drive of the said shaft is obtained by frictionbetween driven wheel or drum on it and a driving wheel or drum onanother shaft said wheels or drums being preferably multi-grooved ontheir faces or otherwise constructed so as to ensure a sufficient grip.

A band brake is fitted over the driven wheel to the shaft of which thecrank of the hammer is attached, or the brake may be over a separatewheel or pulley on the said shaft. This brake is normally in contactwith the driven wheel or pulley which is then stationary with thedriving wheel out of contact. The band brake is connected, preferablyadjustably, by a rod to a foot lever and held down by a spring in such amanner that when the lever is depressed the brake is lifted and thedriving wheel contacts with the driven wheel and thus a friction drivebetween the two is made. The hammer may be adjustably connected to thecrank and obviously the driving shaft may have fast and loose pulleyswith striking gear or other means for entirely stopping the machine whenso required.

My invention is shown by way of example in the accompanying drawings inwhich Fig. 1 is a side view of the machine.

Fig. 2 is a back view of the same machine and Figs. 3 and 4: show thewheels in and out of contact respectively, it being understood that verylittle movement from one position to the other is all that is necessary.

In this example the machine comprises a pedestal 1 on the upper part ofwhich a shaft 2 carrying the driven grooved wheel 3 is fitted.- The sameshaft carries a disc 4 with an eccentric 4 to which the rod 5 of thehammer 6 is connected, the said rod being adjustable at 7. The supportor anvil 8 is positioned below the hammer.

Parallel with shaftQ is a second shafti) A band brake 13 is placed overthe driven wheel 3 and is connected to a rod 14 which is held down by aspring 141$ to normally keep the brake in contact with the wheel. Thisrod is adjustably connected to a foot lever 15 pivoted at '16. Assumingthe machine to be running idle the motion of the shaft 9 is confined tothe wheel 10'but imme diately this wheel is raised into contact withwheel 3 the shaft 2 is rotated and the disc with crank 1 rotates and bythe rod 5 reciprocates the hammer 6. Thus when a workpiece is placedunder the hammer the treadle or lever 15 is depressed and the brake 13is lifted by rod 14, from the wheel 3 and at the same time the wheel 10is raised into contact with the wheel 3 and power from the pulley 11 iscommunicated by shaft 9, wheels 10 and 3, eccentric 4 and rod 5 to thehammer, causing it to strike the workpiece as long as the treadle isheld down.

In Figs. 3 and f preferred forms of mounting the brake and the wheel 10are shown. The brake is fixed at 1'7 and adjustably connected to the rod14L at 18. This rod is held in clamp 19 of arm 20 which is secured tosleeves 21 in brackets 22 and carries the shaft 9. This shaft iseccentrically mounted in the'sleeves 21 with the effeet that when thearm 20 rises the sleeves have slight turning movement and lift the shaft9 sufficiently to bring the wheel 10 into frictional engagement withwheel 3. The arm 20 is connected to spring 1% the tendency of which isto pull down the arm and thus disengage the wheel 10 from wheel 3 andapply the brake.

That I claim is 1. A power hammer operating means comprising a pedestal,two parallel shafts on the pedestal, a driving wheel on one shaft and adriven wheel on the other shaft, treadle-operated means for shifting theshaft carrying the driving wheel, a spring to shift the shaft when thetreadle is not operated, and means on the shaft of the driven wheel foroperating a hammer.

2. A power hammer operating means com prising a pedestal, two parallelshafts on the pedestal, a driving wheel on one shaft and a driven wheelon the other shaft, treadle-operated means for shifting the shaftcarrying the driving wheel, a spring to shift the shaft when the treadleis not operated, a band brake over the driven wheel adapted to be liftedby the actuation of the treadle and to be applied by the spring, andmeans on the shaft of the driven wheel for operating a hammer.

3. A power hammer operating means comprising a pedestal, a shaft mountedon the pedestal, a driven wheel on the shaft, pivoted arms carryingsleeves capable of rotation in brackets mounted on the pedestal, asecond shaft eccentrically mounted in the sleeves, a driving wheelmounted on the sec- 0nd shaft, a rod connected to the arms, a treadleconnected to the rod and adapted to shift the arms in one direction tobring the said two wheels into frictional engagement, a spring adaptedto shift the arms in the opposite direction when the treadle isreleased,

and means on the shaft of the driven wheel for operating a hammer.

l. A power hammer operatlng means comprising a pedestal, a shaft mountedon the pedestal, a driven wheel on the shaft, pivoted arms carryingsleeves capable of rotation in brackets mounted on the pedestal, asecond shaft eccentrically mounted in the sleeves, a driving pulleymounted on the second shaft, a rod connected to the arms, a treadleconnected to the rod and adapted to shift the arms in one direction tobring the two said wheels into frictional engagement, a spring adaptedto shift the arms in the opposite direction when the treadle isreleased, a brake connected to the rod and adapted to be removed whenthe treadle is actuated and to be applied by the spring acting throughthe rod when the treadle is released, and means on the shaft of thedriven wheel for operating a hammer.

In witness whereof I have hereunto set my hand in presence of twowitnesses.

GEORGE FRASER.

lVitnesses:

ELIZABETH JEAN hoUsToN, PETER VVA'rsoN ROBERTSON.

